`Redhaven' Peach Impact Damage Thresholds

Abstract

<jats:p>`Redhaven' peaches [<jats:italic>Prunus persica</jats:italic> (L.) Batsch] were dropped onto several impact surfaces to determine impact conditions that initiate bruising. After impact, the peaches were tested for flesh firmness and sorted into firm, soft, and very soft groups for bruise analysis. The drop height that did not bruise decreased as fruit softened. The peach shoulder area bruised most easily. A drop of only 8 mm onto a hard surface initiated bruising on a soft peach, whereas a Poron 15250 cushion could protect the peach for a ≤85-mm drop. Impact damage threshold estimates were developed for the three flesh firmness conditions. The threshold estimates and impact history information collected by an instrumented sphere can be used to develop handling equipment design and operation guidelines that essentially avoid impact bruises on peaches.</jats:p>

The effect of impact and fruit properties on the bruising of peach

“…A higher firmness or failure stress for stiffer fruits means that they are more resistant to bruising. Several researchers observed increased physical damage with soft peaches (Lin and Brusewitz, 1994;Schulte et al, 1994;Gorny et al, 1998;Metheney et al, 2002). Fruits with higher stiffness will have shorter contact times, which reduce the risk to develop bruises (Van linden et al, 2006a).…”

“…Bruise extension is usually described in terms of bruise volume (Blahovec and Paprstein, 2005). Statistical bruise prediction models described in the literature for peach are restricted to the effect of peach ripeness on bruise susceptibility (Hung and Prussia, 1989;Schulte et al, 1991;Vergano et al, 1991;Lin and Brusewitz, 1994;Delwiche et al, 1996;Diezma et al, 2006). The force response of an elastic sphere impacting a rigid surface is governed by the impacting velocity, mass, radius of curvature, elastic modulus, and Poisson ratio of the sphere.…”

“…It has been found that the impact of a fruit on a rigid surface can be closely modeled by the impact of an elastic sphere and that the firmness of a fruit has a direct effect on the impact force response (Desmet et al, 2004;Diezma et al, 2006). It would seem that bruising would be influenced by fruit mass, energy absorbed by the fruit during impact, and impact velocity, the latter is due to the viscoelastic nature of fruit tissue (Schulte et al, 1991;Lin and Brusewitz, 1994).…”

Effect of Road Vibrations on the Mechanical Properties of Olive Fruit During Transport

“…A lot of research has been done related to mechanical damage of agriculture products such as apples [10], peaches [11], tomatoes [12], potatoes [13] and pomegranates [14]. In a study to reduce the modulus of tomato elasticity, it was concluded that during transportation, the young modulus of the fruit decreases significantly [15].…”

PERFORMANCE OF AN INSTRUMENT DESIGNED FOR, AND EVALUATION OF METHODS TO ASSESS, PEACH FRUIT IMPACT BRUISE SUSCEPTIBILITY1

“…The final two measures serve as indicators of bruising severity and often require exposure of fruit to higher impact energies to demonstrate the presence of a visible bruise. Bruise susceptibility information has recently been used to develop bruising thresholds, in terms of peak acceleration velocity (measured with an Instrumented Sphere) for peaches (Schulte et al 1994), using bruise occurrence as an indicator of susceptibility and for apples (Pang et al 1994) and peaches (Lin and Brusewitz 1994) using bruising severity as an indicator of susceptibility.…”